function s1_generate_a_series_of_files(){
  for x in {1...100};
   do 
      echo $x>/tmp/new_file $x;
   done
}
function s2_list_4_files_in_long_format_about_account_and_group(){
  ls -l /etc/{passwd,shadow,group,gshadow} |
  sort 
}
function s3_find_items_related_to_given_username(){
grep -h $1/etc/{passwed,shadow} |sort 
}
function s4_find_items_related_to_given_group_name(){
 grep -h $1/etc/{group,gshadow} |sort
}
function s5_create_group_for_given_group_names(){
 groupadd rnd
 groupadd itoperation
}
function s6_create_users_and_set_their_group_as_required(){
 useradd -G rnd adam 
 useradd -G rnd bob 
 useradd -G itoperation calvin 
 useradd -G itoperation david
 useradd adam 
 useradd bob
 useradd calvin
 useradd david
useradd edward
}
function s7_change-users-shell(){
usermod -s/usr/bin/sh adam
usermod -s/usr/bin/sh edward
}
function s8_set_password_policy(){
passwd -n 10 -x 60 -w 10 adam
 passwd -n 10 -x 60 -w 10 bob
 passwd -n 10 -x 60 -w 10 david
 passwd -n 10 -x 60 -w 10 calvin
 passwd -n 10 -x 60 -w 10 edward
}
function s9_set_password_for_five_users(){
  usenames=(adam bob calvin david edward)
  passwords=("$1""$2""$3""$4""$5")
 for((i=0;i<5;i++));
 do
 echo "${username[i]}:${passwords[$i]}"chpasswd
 done
}
function s10_lock_bobs_password(){
usermod -L bob
}
function s11_include_adam_into_wheel_groupup(){
 usermod -a -G wheel adam
}
function s12_change_files_permission(){
 for((i=1;i<=100;i++));
 do
 filename="tmp/new_file${i}"
 echo -n "$i">$filename
 if(($i%3==0))
  then
   chmod u+rw,g+rw,o-rwx"$filename";
  fi
   done
}


